The Ramblings of a Middle Aged Fertility Physician whose life revolves around Eggs, Sperms & Embryos....
Tuesday, October 23, 2007
Risks Associated With Fertility Medications
The controlled "superovulation" techniques used in IVF are designed to stimulate the ovaries to produce several eggs (oocytes) rather than the usual single egg as in a natural cycle. Multiple eggs increase the potential availability of multiple embryos (fertilized eggs) for transfer and ultimately increase the probability of conception. The medications required to boost egg production may include, but are not limited to the following: Lupride/Gonapeptyl (gonadotropin releasing hormone-agonist), Antagon or Cetrotide (gonadotropin releasing hormone-antagonist), Menopur, Bravelle or Gonal-F (FSH, follicle stimulating hormone), GMH(combination of FSH and LH, luteinizing hormone), and Choragon or Ovidrel(hCG, human chorionic gonadotropin). Each is administered by injection only. Most medications are given subcutaneously (beneath the skin), though some are intramuscular injections (into the muscle). Risks associated with injectable fertility medications may include but are not limited to, tenderness, infection, hematoma, and swelling or bruising at the injection site. Risks associated with the medications may include, but are not limited to, allergic reactions, hyperstimulation of the ovaries (mild, moderate or severe), failure of the ovaries to respond and cancellation of the treatment cycle.
There are situations that can occur during a stimulation that may necessitate canceling your IVF cycle and stopping treatment for a period of time. This occurs because the ovaries produce either too many or too few eggs in response to drug stimulation protocol. Although we realize that this can be a big disappointment, at times it is necessary to discontinue the use of the medications to avoid the possibility of complications and to afford you the best chance of future success. If canceling the cycle becomes necessary, you will be told to stop your injections. No hCG injection will be given and no egg retrieval will occur. You will be asked to schedule an appointment with your physician to make decisions regarding future treatment cycles.
When ovulation induction medications are used in fertility therapy, the ovaries are coaxed to produce more than one egg to the point of maturity. Consequently, hormone levels of estrogen and progesterone reach much higher than normal values. When the estrogen level becomes mildly to moderately elevated, side effects that may be experienced include, but are not limited to, fluid retention with slight transient weight gain, nausea, diarrhea, pelvic discomfort due to enlarged cystic ovaries, breast tenderness, mood swings, headache and fatigue.
If the estrogen level rises excessively and hCG is administered to trigger final maturation of the eggs, the following more serious complications may result:
Excessive fluid retention with fluid in the abdomen and/or chest cavity;
Thrombosis of arteries and/or veins (formation of blood clots) which may lead to stroke, embolus, or potentially fatal complications;
Abnormally enlarged ovaries, which have the possibility of rupturing or twisting (a surgical emergency)
Any of the three problems listed above may require prolonged hospitalization.
Given the potential for such severe complications, it is important that we carefully monitor the response to these medications. This monitoring also allows your physician to determine when the eggs are ready for the next stage, oocyte (egg) retrieval. Monitoring includes frequent blood drawing for estradiol (estrogen) and possibly progesterone, LH and FSH levels. These blood tests will take place over approximately a twelve-day period. Risks associated with blood drawing may include, but are not limited to:
Pain at the site of needle stick
Tenderness or infection of the skin
Bruising or scarring of the site of blood draw
Development of a blood clot in the vein (thrombosis, thrombophlebitis)
The second portion of the monitoring phase in IVF involves the use of intravaginal ultrasound to track follicular growth. The eggs develop inside fluid-filled cysts of the ovaries called follicles, which enlarge as the eggs mature. Ultrasound studies usually begin after an estrogen response has been measured and continue on a frequent basis until oocyte (egg) retrieval. The ultrasound studies are performed using a vaginal probe. Vaginal sonograms carry no appreciable risk but may cause slight discomfort, particularly as you near the point of ovulation.
Monday, October 22, 2007
Intracytoplasmic Sperm Injection (ICSI)
Through the controlled application of ovarian hyperstimulation, it is current practice to time the retrieval of mature oocytes (eggs) from a woman's ovary. The yield may vary anywhere from one to 30 or more eggs that may be retrieved depending on the responsiveness of the ovaries to the gonadotropins used to stimulate them. These eggs are gathered by the embryologist into an appropriately balanced salt solution and maintained at body temperature (37°C) until such time as they are ready to be inseminated. Meanwhile, a sample of semen containing the sperm destined to be used for each specific set of eggs is collected and processed by cell separation techniques to provide as clean and active a sample of sperm as possible. A major emphasis of the IVF laboratory is directed toward guaranteeing that the correct sperm go with the right eggs through good labeling and check systems. Ultimately, following several hours in culture, eggs and sperm can be mixed and allowed to bind and fertilize in a relatively natural fashion. Depending on the quality and maturity of both eggs and sperm, it is common for fertilization rates to vary considerably relative to the original number of eggs collected. Twenty eggs retrieved in no way guarantees 20 embryos. Likewise, 20 fertilized eggs in no way guarantees that there will be 20 embryos of sufficient quality for both cryopreservation and fresh transfer to the woman's body.
Central to the question of how many embryos are actually utilized in any IVF treatment cycle is the period during which the embryos are cultured in vitro. This can be as little as one day, or up to five in the case of blastocyst growth and transfer. Assuming that culture conditions are relatively optimal, there is less and less reason not to culture embryos throughout their pre-implantation stages to allow the embryos to "select" themselves for transfer or cryopreservation. The blastocyst is the term given to the very last stage of an embryo prior to it implanting into the endometrial lining of the uterus. The poorer the rates of blastocyst growth are, the more restricted the choice of embryo is at this stage of development. In any event, growth of any embryos to the blastocyst stage improves the level of discrimination of embryo viability available to the embryologist, and is key to reducing the numbers of embryos used for uterine transfer. The more confidence a clinic has in the viability of the embryos it transfers, the less need there is for multiple transfers of three or more embryos. Thus with the transfer of three or less embryos, the risk of multiple pregnancies is significantly reduced, in turn minimizing risks of pregnancy loss or fetal abnormalities common in multi-fetal pregnancies.
Micromanipulation is the technique whereby sperm, eggs and embryos can be handled on an inverted microscope stage, performing minute procedures at the microscopic level via joysticks that hydraulically operate glass microtools. Micro-manipulation first saw clinical use in IVF for purposes of assisted fertilization in the treatment of male factor infertility, where fertilization potential was low in cases of poor sperm quality. The ultimate evolution of this approach has been the development of the single sperm injection procedure referred to as Intracytoplasmic Sperm Injection, or ICSI. Sperm of virtually any quality and from any level of the male reproductive tract may be used with the only criterion for use being that the sperm is alive even if it is not moving (motile). Dead sperm may be able to achieve fertilization; however, the DNA or genetic material from such sperm is too degenerate to form a viable embryo. Immature sperm from the testicle or the epididymis can be retrieved for use with ICSI for men who possess no sperm in their ejaculated semen (azoospermia). This azoospermia is either due to an obstruction in the tract (obstructive), or to extremely low production of sperm in the testicle itself (non-obstructive). In certain cases, men may produce sufficient sperm, but they do not survive to the point of ejaculation (necrozoospermia). Consequently, instead of using non-viable sperm from the ejaculate, testicular biopsy will provide a ready source of freshly produced viable sperm.
With the almost unlimited potential to achieve some level of fertilization with ICSI regardless of sperm quality, it would seem that male factor infertility would no longer be of concern. It must be noted, however, that sub-fertility in men can be related to certain numerical and structural defects of the chromosomes and, therefore, there is a strong recommendation for all couples that achieve pregnancies from ICSI to undergo prenatal screening. In certain cases of obstructive azoospermia, there is a higher incidence of cystic fibrosis in the male. Hence, before embarking upon treatment of the more extreme forms of male factor infertility, it is advisable to have some cytogenetic screening performed. Incidentally, very subtle compromise in sperm quality may well be responsible for a marginally lower embryonic viability rate and a slightly higher early miscarriage rate even if such embryos implant. Such observations have led to the suggestion that the technique ICSI itself is at fault; but this misses the point that ICSI per se is not causing the problem, merely facilitating the use of sperm, which under other circumstances would never have even achieved fertilization.
The use of ICSI is now routinely applied to a range of clinical situations wherever there is a possibility that conventional in vitro fertilization may be suppressed or not occur. Such situations include the following: idiopathic or unexplained fertility; hyper-responsive ovarian stimulation cases where egg quality may be reduced; post-thaw sperm samples that survive poorly; post-thaw egg insemination; generation of embryos for pre-implantation genetic screening where embryos "clean" from any extraneous contaminating sperm is needed; or, indeed, any case where there is an extreme need to maximize normal fertilization, for example, when a woman has only a few eggs retrieved. It is possible to "rescue" cases following complete failed conventional fertilization with ICSI. The viability potential of these "late-fertilized" embryos is approximately half of timely fertilized embryos; nevertheless, they do generate successful live births. ICSI has become such a common feature of IVF therapy that it is fast becoming the insemination technique of choice.
Sunday, October 21, 2007
Two Lawyers
Two lawyers had been life long friends: they were partners and shared everything , including their hot-blooded secretary .
One day the secretary announced she was pregnant. They told her not to worry and assured her that they would pay all medical costs and would act as co-fathers when the child was born and provide all expenses thereafter.
The day of delivery arrived. Both the lawyers were at the hospital pacing the floor in the waiting room. Finally one of them said, "I can't take this, I'm going down to sit in my car and wait there. Please come down and tell me as soon as the child is born!"
The partner agreed to do that. About an hour later the partner approached the car with a very grave look on his face.
"What happened ?" asked the waiting car occupant.
The other partner announced, "They were twins and mine died!"
Saturday, October 20, 2007
The Italian Don
An old Italian Mafia Don is dying and he calls his grandson to his bed!"
Lissin-a me. I wanna for you to taka my chrome plated 38 revolver so you will always remember me."
"But grandpa, I really don't lika guns. Howzabout you leava me your Rolex watch instead?"
"Looka here sonnie. Somma day you gonna runna da business.....you gonna have a beautifula wife, lotsa money, a biga home and maybe a couple a bambinos."
"Somma day you gonna comma home and maybe find you wife inna bed with another man.
Whadda you gonna do then....... pointa to you watch and say "Times up"?"
Lissin-a me. I wanna for you to taka my chrome plated 38 revolver so you will always remember me."
"But grandpa, I really don't lika guns. Howzabout you leava me your Rolex watch instead?"
"Looka here sonnie. Somma day you gonna runna da business.....you gonna have a beautifula wife, lotsa money, a biga home and maybe a couple a bambinos."
"Somma day you gonna comma home and maybe find you wife inna bed with another man.
Whadda you gonna do then....... pointa to you watch and say "Times up"?"
Friday, October 19, 2007
Blastocyst Embryo Transfer
Blastocyst transfer achieved the first IVF human pregnancy. Blastocyst transfer is claimed to be more physiological than pronucleate or cleaved-embryo transfer is as it mimics nature more closely. As the embryo advances in the development, after 5-6 days it becomes a blastocyst(see picture). This has an outer thin layer of cells, which will later form the placenta, and an inner cell mass, which will develop into the fetus. A blastocyst has about 120 cells. A blastocyst gives a better idea of the competence of an embryo and has a higher chance of implantation than a cleaved embryo. In conventional culture medium, about 20% of embryos will develop into blastocysts. Recently, the use of sequential culture medium (the embryos are cultured in different media according to their stage of growth) has enabled a larger number of embryos to develop into blastocysts. However, up to 40% of patients will not grow blastocysts and will not have blastocyst embryo transfer. The rationale behind a blastocyst transfer is that an embryo, which has failed to reach the blastocyst stage, would be unlikely to have resulted in a pregnancy. However, if it reaches the blastocyst stage it has about 50% chance of implanting. So the improved implantation rates following blastocyst transfer is due to selection of the best embryos.
Why then do 50% of the blastocysts fail to implant? A defective blastocyst (e.g. chromosomal abnormalities) is a possible cause; a non-receptive endometrium is another cause. Blastocyst embryo transfer into the uterine cavity is performed about 5-6 days after egg collection. Transfer of one or two blastocysts is recommended to avoid high-order multiple pregnancies. Supernumerary blastocysts can be frozen for future use.
Blastocyst transfer is recommended for patients who had repeatedly failed to achieve a pregnancy following the transfer of good quality cleaved embryos (If the embryo arrests and did not develop to blastocyst, this may indicate a potential egg problem). Patients who wish to achieve a pregnancy without the risk of multiple pregnancies will benefit from a single blastocyst transfer. Patients who do not wish to have their spare embryos frozen for whatever reasons may be advised to have blastocyst transfer. About 10% of the embryos that fail to develop to blastocyst in vitro may have done so if replaced inside the womb on day 2 or 3. Up to 40% of patients will not have blastocysts available for transfer. Freezing spare blastocysts is not as good as freezing cleaved embryos. But, with the advent of Vitrification, high pregnancy rates have been reported from countries such as Spain & Japan. We, at Rotunda have just embarked upon our Vitrification Program, which is as yet in a nascent stage
Thursday, October 18, 2007
The Guinness Moms?
It would appear that the quest for motherhood is for some, a desire that fails to subside with age. Empowered by new technologies such as IVF treatments, women are increasingly seeking the assistance of fertility clinics to fulfil their aim of bearing a child when their biological clock has ground to a halt. For single women in Japan, however, this type of assistance is not so easy to come by. Strict laws in the field of surrogacy and artificial insemination are imposed due to the country's traditional approach to human reproduction. As a result, fertility treatment is provided almost exclusively to married couples.
Undeterred, a single 60-year old Japanese woman has taken such restrictions into her own hands. The Times newspaper has reported this week that the woman, who wished to remain anonymous, is now in her fifteenth week of pregnancy after travelling to the United States for fertility treatment. She is believed to be the first and oldest single woman to conceive from a donated egg. The use of donated eggs is strictly limited to married couples under a Japanese medical guideline.
After a series of unsuccessful attempts to find a doctor in Japan willing to handle the pregnancy, Yahiro Netsu, a gynaecologist at The Suwa Maternity Clinic in Nagano, central Japan, has stepped in to help. Speaking to the Associated Press, Mr Netsu confessed that the decision had been a tough one, especially as her age and single status meant that the pregnancy was a high risk and an uncertain future for the child. The gynaecologist, however, was won over by the woman's desire to bear a child in spite of her age. He said:'But she wanted a child, and I decided to do all I can to help her through
expected difficulties'.
Although the pregnancy has yet to reach a happy conclusion, Mr Netsu and his patient should take heart from the birth of a healthy baby boy born last summer to a British woman, aged 62. Dr Patricia Rashbrook, a psychiatrist from Lewes, East Sussex, conceived using a donor egg after her fifth attempt at IVF. Her son, nicknamed JJ, weighed a healthy 6 pounds and 10 ounces. But with the trend for older mothers continuing, it would appear that even Dr Rashbrook has been usurped in the trophy for 'The world's oldest mum'. This accolade is believed to go to a 67-year old Spanish woman who gave birth to
twin boys following IVF treatment last year. She is closely followed by Adriana Iliescu, from Romania, who had a daughter called Eliza Maria in January in 2005 at the age of 66.
Undeterred, a single 60-year old Japanese woman has taken such restrictions into her own hands. The Times newspaper has reported this week that the woman, who wished to remain anonymous, is now in her fifteenth week of pregnancy after travelling to the United States for fertility treatment. She is believed to be the first and oldest single woman to conceive from a donated egg. The use of donated eggs is strictly limited to married couples under a Japanese medical guideline.
After a series of unsuccessful attempts to find a doctor in Japan willing to handle the pregnancy, Yahiro Netsu, a gynaecologist at The Suwa Maternity Clinic in Nagano, central Japan, has stepped in to help. Speaking to the Associated Press, Mr Netsu confessed that the decision had been a tough one, especially as her age and single status meant that the pregnancy was a high risk and an uncertain future for the child. The gynaecologist, however, was won over by the woman's desire to bear a child in spite of her age. He said:'But she wanted a child, and I decided to do all I can to help her through
expected difficulties'.
Although the pregnancy has yet to reach a happy conclusion, Mr Netsu and his patient should take heart from the birth of a healthy baby boy born last summer to a British woman, aged 62. Dr Patricia Rashbrook, a psychiatrist from Lewes, East Sussex, conceived using a donor egg after her fifth attempt at IVF. Her son, nicknamed JJ, weighed a healthy 6 pounds and 10 ounces. But with the trend for older mothers continuing, it would appear that even Dr Rashbrook has been usurped in the trophy for 'The world's oldest mum'. This accolade is believed to go to a 67-year old Spanish woman who gave birth to
twin boys following IVF treatment last year. She is closely followed by Adriana Iliescu, from Romania, who had a daughter called Eliza Maria in January in 2005 at the age of 66.
Wednesday, October 17, 2007
Polycystic Ovary Syndrome
Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women, affecting an estimated five to ten percent women of reproductive age in India. For women trying to conceive a child, PCOS is a serious, common cause of infertility - nearly half of all female factor infertility cases can be traced to PCOS. New medical insight into the disease has led to treatment options, including insulin-reducing ovulation medication (Clomiphene, Letrozole, Metformin), dietary changes (low glycemic diet) and surgery (ovarian drilling), which have proven successful and allow many women to overcome PCOS and conceive a child naturally, while reducing the risk of miscarriage. Women who undergo treatment for PCOS but are still unable to conceive naturally often turn to assisted reproductive technologies, including IVF, and experience high pregnancy success rates. At Rotunda, our physicians specialize in this common, yet often misunderstood cause of infertility. We work closely with each patient to understand her specific medical case and personal goals, including weight loss, pregnancy or improving general health, and develop a holistic approach to reach those goals. Oftentimes, the road to overcoming PCOS is not an easy one and it takes a strong commitment from both the patient and the physician. The team at Rotunda is committed to supporting our patients every step of the way. I have just published a monograph on "PCOS" which was released by Anshan Publications (www.anshan.co.uk).
Polycystic ovary syndrome is characterized by anovulation (irregular or absent menstrual periods) and hyperandrogenism (elevated serum testosterone and androstenedione). Patients with this syndrome may complain of abnormal bleeding, infertility, obesity, excess hair growth, hair loss and acne. In addition to the clinical and hormonal changes associated with this condition, vaginal ultrasound shows enlarged ovaries with an increased number of small (6-10mm) follicles around the periphery (PCO like ovaries). While ultrasound reveals that polycystic appearing ovaries are commonly seen in up to 20% of women in the reproductive age range, Polycystic Ovary Syndrome (PCOS) is a estimated to affect about half as many or approximately 6-10% of women. The condition appears to have a genetic component and those effected often have both male and female relatives with adult-onset diabetes, obesity, elevated blood triglycerides, high blood pressure and female relatives with infertility, hirsutism and menstrual problems.
Presently, we do not understand why one woman who demonstrates polycystic appearing ovaries on ultrasound has regular menstrual cycles and no signs of excess androgens while another develops PCOS. One of the major biochemical features of polycystic ovary syndrome is insulin resistance accompanied by compensatory hyperinsulinemia (elevated fasting blood insulin levels). There is increasing data that hyperinsulinemia produces the hyperandrogenism of polycystic ovary syndrome by increasing ovarian androgen production, particularly testosterone and by decreasing the serum sex hormone binding globulin concentration. The high levels of androgenic hormones interfere with the pituitary ovarian axis, leading to increased LH levels, anovulation, amenorrhea, recurrent pregnancy loss, and infertility. Hyperinsulinemia has also been associated high blood pressure and increased clot formation and appears to be a major risk factor for the development of heart disease, stroke and type II diabetes.
There is little agreement when it comes to how PCOS is diagnosed. Most physicians will consider this diagnosis after making sure you do not have other conditions such as Cushing's disease (overactive adrenal gland), thyroid problems, congenital adrenal hyperplasia or increased prolactin production by the pituitary gland. TSH, 17-hydroxyprogesterone, prolactin and a dexamethasone suppression test may be advisable. After reviewing your medical history, your physicians will determine which tests are necessary. If you have irregular or absent menstrual periods, clues from the physical exam will be considered next. Your height and weight will be noted along with any increase facial or body hair or loss of scalp hair, acne and acanthosis nigricans (a discoloration of the skin under the arms, breasts and in the groin). Elevated androgen levels (male hormones), DHEAS or testosterone help make the diagnosis. A two hour insulin and glucose tolerance test will be obtained. Many physicians tell their patients that insulin values are normal, when in fact the value indicates that insulin may be playing a role in stimulating the development of PCOS. Most labs report levels less than 25-30 miu/ml as normal, while in fact, levels over 10miu/ml on a fasting blood sample suggests that PCOS may be related to hyperinsulinism. As women with polycystic ovary syndrome may be a greater risk for other medical conditions, testing for cardiovascular risk factors such as blood lipids should also be carried out.
Traditional treatments have been difficult, expensive and have limited success when used alone. Infertility treatments include weight loss diets, ovulation medications (Clomiphene,Letrozole, Menopur, Gonal-F), ovarian drilling surgery and IVF. Other symptoms have been managed by anti-androgen medication (birth control pills, spironolactone, flutamide or finasteride).
Ovarian drilling can be performed at the time of laparoscopy. A laser fibre or electrosurgical needle is used to puncture the ovary 6-8 times(see picture). This treatment results in a dramatic lowering of male hormones within days. Studies have shown that up to 80% will benefit from such treatment. Many who failed to ovulate with letrozole or metformin therapy will respond when rechallenged with these medications after ovarian drilling. Interestingly, women in these studies who are smokers, rarely responded to the drilling procedure. Side effects are rare, but may result in adhesion formation or ovarian failure if the procedure is performed by an inexperienced surgeon.
For women in the reproductive age range, polycystic ovary syndrome is a serious, common cause of infertility, because of the endocrine abnormalities which accompany elevated insulin levels. There is increasing evidence that this endocrine abnormality can be reversed by treatment with widely available standard medications which are leading medicines used in this country for the treatment of adult onset diabetes, metformin 850 mg two times per day or 1000mg twice daily with meals), Hyponiid (Charak Pharma) (Which is a D-Chiro Inositol containing Indian Ayurvedic Medication) or a combination of these medications. These medications have been shown to reverse the endocrine abnormalities seen with polycystic ovary syndrome within 10-12 months. They can result in decreased hair loss, diminished facial and body hair growth, normalization of elevated blood pressure, regulation or menses, weight loss, reduction in cardiovascular risk factors, normal fertility, and a reduced risk of miscarriage. We have seen pregnancies result in less than 18 months in women who conceived spontaneously at home. By twenty-four months over 90% of women treated with insulin-lowering agents, diet and exercise will resume regular menses.
The medical literature suggests that the endocrinopathy in most patients with polycystic ovary syndrome can be resolved with insulin lowering therapy. This is clinically very important because the therapy reduces hirsutism, obesity, blood pressure, triglyceride levels, elevated blood clotting factors and facilitates re-establishment of the normal pituitary ovarian cycle, thus often allowing resumption of normal ovulatory cycles and pregnancy. We know the polycystic ovary syndrome is associated with increased risk of heart attack and stroke because of the associated heart attack and stroke risk factors, hypertension, obesity, hyperandrogenism, hypertriglyceridemia, and these are to a large degree resolved by therapy with these medications. Side effects are rare. Although metformin, rosiglitazone and pioglitazone lower elevated blood sugar levels in diabetics, when given to nondiabetic patients, they only lower insulin levels. Blood sugar levels will not change. In fact, episodes of "hypoglycemic attacks" appear to be reduced.
When first starting Metformin, people will often experience upset stomach or diarrhea (usually loosely formed stools) which usually resolves after the first couple of weeks. This side effect can be minimized by taking metformin with the heaviest meal of the day and starting with a low dose. I recommend that our patients start with one 850 mg pill daily the first week and increase to twice a day during the second week. Patients with reduced renal function (creatinine >1.5 or creatinine clearance <60%) are at a higher risk for a rare side effect of metformin therapy called lactic acidosis, and the drug should be given cautiously, if at all, to such patients. Patients taking metformin should notify their physician and discontinue the medication. Pioglitazone or Rosiglitazone belong to a class of medications called PPAR gamma agonists. They enhance the ability of smooth muscle to metabolize sugar, thereby reducing insulin resistance. The FDA has recently reviewed the safety of troglitazone (and reports that 35 patients out of approximately 1.5 million have either died or required liver transplant.) Therefore Troglitazone has been removed from the market. As the new alternatives to Troglitazone, Rosiglitazone and Pioglitazone are metabolized by different liver enzymes, experience has shown that these medications appear to pose minimal risk of hepatotoxicity.
Transvaginal follicular studies are done to determine if you are ovulating.You will be asked to return three months after initiating therapy. If you have ovulated, therapy may be continued another three months to see if you will conceive. Re-evaluation will include measurements of lab tests that were abnormal at the initial evaluation. If the laboratory studies are still abnormal, metformin may be increased up to 1000 mg three times daily or rosiglitazone may be substituted alongwith addition of higher doses of Hyponiid. If the laboratory studies are normal but ovulation has not occured, a trial of letrozole may be considered. We have seen that women who were unable to ovulate on up to 250 mg of clomiphene ovulate when very low doses of clomiphene or letrozole are used in conjunction with metformin or PPARgamma therapy. Laparoscopic ovarian drilling may be considered for those women where other indications for laparoscopy are present.
While safety during pregnancy has not yet been established, reports have been published of patients who continued on metformin during their entire pregnancy and one who remained on a glitazone have delivered normal babies. There are no reports of abnormal babies in women who conceived using metformin and all resulting babies were normal. Metformin is a category B medication. This means that insufficient human data is available but no credible animal data suggesting a teratogenic (could produce birth defects) risk. Although to the best of our present knowledge the risk of birth defects would be small, it must also be noted that maternal diabetes has been associated with an increased risk of birth defects and the underlying elevated insulin levels may lead to birth defects if not corrected.
While the most prudent policy may be to avoid the use of these medications during pregnancy until more data on pregnancy outcome is available, the risk of miscarriage may be reduced by continuing metformin during the pregnancy. Women with PCOS who conceive either spontaneously or after ovulation induction have a much higher risk of miscarriage. Hypersecretion of LH was thought to cause chromosomally abnormal eggs leading to an increased risk of miscarriage. But a Japanese study found that PCOS was more common in women whose prior loss was associated with normal chromosomes. Others have suggested that high androgen levels may be a contributory factor. Homburg has shown that miscarriage rates after ovulation induction or IVF is decreased when women are pretreated with a GnRH-agonist such as Synarel, Lupron or Zoladex.
Hyperinsulinemia may be a contributing factor in the higher rate of miscarriage. Elevated levels of insulin interfere with the normal balance between factors promoting blood clotting and those promoting breakdown of the clots. Increases in plasminogen activator inhibitor activity (PAI) associated with high insulin levels may result in increased blood clotting at the interface between the uterine lining (endometrium) and the placenta. This could lead to placental insufficiency and miscarriage.
There are no placebo-controlled clinical trials to indicate whether pregnancy outcomes are improved in pregnancies that result from the use of insulin-lowering medications or whether pregnancy outcomes are better in those who continue metformin throughout the pregnancy or those who discontinue. At present there is insufficient data to routinely advise continuation of metformin during pregnancy. As an alternative to continuing metformin therapy, those women with increased risk of abnormal blood clotting may benefit from baby aspirin, folate supplementation and low molecular weight heparin therapy.
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