Polycystic Ovary Syndrome (PCOS) is a common endocrine disorder affecting women of reproductive age, impacting an estimated 6% to 15% of this population. This hormonal imbalance can significantly influence a woman’s ability to conceive and carry a pregnancy to term. While the exact cause of PCOS is not fully understood, it is recognized as one of the most frequent causes of infertility. Most individuals with PCOS can achieve pregnancy, often with medical support.
Mechanisms Impairing Conception
PCOS primarily hinders conception through hormonal imbalances and their downstream effects on the reproductive system. Elevated levels of androgens are a characteristic feature of PCOS. These increased androgen levels, along with insulin resistance, disrupt the delicate hormonal environment necessary for regular ovulation.
Insulin resistance, where the body’s cells do not respond effectively to insulin, often accompanies PCOS. This leads to higher insulin levels in the bloodstream, which can then stimulate the ovaries to produce even more androgens. This excess insulin can also interfere with the liver’s production of sex hormone-binding globulin (SHBG), further increasing the amount of active testosterone in the body. The combined effect of these hormonal disruptions prevents the ovaries from consistently releasing a mature egg, a process known as anovulation. Anovulation is the most common cause of infertility in women with PCOS.
The hormonal environment in PCOS can also affect egg quality. While PCOS may not directly impair egg quality, the associated conditions such as insulin resistance, elevated androgen levels, and imbalances in luteinizing hormone (LH) and follicle-stimulating hormone (FSH) can indirectly reduce egg viability. These factors can lead to poor egg maturation. Additionally, hormonal imbalances in PCOS can impact the receptivity of the uterine lining, potentially hindering the successful implantation of an embryo.
Impact on Pregnancy Journey
Beyond the challenges of conception, individuals with PCOS may face an increased risk of complications once pregnancy is achieved. The risk of miscarriage is higher in women with PCOS. This elevated risk is linked to underlying hormonal imbalances, insulin resistance, and potential endometrial dysfunction. High blood glucose levels can also contribute to an increased chance of miscarriage.
Gestational diabetes, a form of diabetes that develops during pregnancy, is more common in women with PCOS. This condition requires careful monitoring and management to prevent complications for both the mother and the baby. There is also an increased risk of preeclampsia, a serious condition characterized by high blood pressure and organ damage after 20 weeks of pregnancy. Women with PCOS have a higher likelihood of developing preeclampsia.
PCOS is associated with a higher risk of preterm birth. Studies indicate that women with PCOS have a significantly increased odds of preterm delivery. This heightened risk is often due to spontaneous preterm labor.
Pathways to Pregnancy with PCOS
Despite the challenges, various strategies can improve the chances of conception and a healthy pregnancy for individuals with PCOS. Lifestyle modifications are often the first line of approach, focusing on diet, exercise, and weight management. A healthy diet can help regulate insulin levels and improve hormonal balance. Regular physical activity, including both aerobic exercise and strength training, can enhance insulin sensitivity and promote more regular menstrual cycles. Even a modest weight reduction can restore ovulation and improve fertility outcomes in overweight women with PCOS.
When lifestyle changes alone are not sufficient, medications can be used to induce ovulation. Common oral medications include clomiphene citrate and letrozole. Clomiphene citrate works by blocking estrogen receptors, prompting the body to produce more follicle-stimulating hormone (FSH) to stimulate egg release. Letrozole, an aromatase inhibitor, lowers estrogen production, which in turn increases FSH and can induce ovulation.
If oral medications are ineffective, injectable gonadotropins may be prescribed to directly stimulate follicle growth in the ovaries. Metformin can also be beneficial in improving insulin sensitivity and ovulation rates in some women with PCOS.
Assisted Reproductive Technologies (ART), such as In Vitro Fertilization (IVF), provide further options for individuals with PCOS. IVF involves retrieving eggs, fertilizing them in a laboratory, and then transferring the resulting embryo into the uterus. While there might be a higher risk of ovarian hyperstimulation syndrome (OHSS) with IVF in PCOS, overall pregnancy and live birth rates are often comparable to those in individuals without PCOS. Close medical supervision throughout pregnancy is important to manage potential risks like gestational diabetes and preeclampsia.