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Pregnant women who contract the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) face an elevated risk of preterm birth, and their newborns are more prone to stillbirth or admission to a neonatal unit. Despite the World Health Organization declaring the end of the coronavirus disease 2019 (COVID-19) pandemic as a global health emergency in May 2023, pregnant women continue to contract SARS-CoV-2. Limited information is available on the impact of SARS-CoV-2 infection in early pregnancy on pregnancy outcomes. Additionally, understanding the safety of vaccination is crucial. Current evidence suggests that SARS-CoV-2 infection in early pregnancy does not seem to heighten the risk of miscarriages. Moreover, vaccinations have demonstrated efficacy in safeguarding both pregnant women and their pregnancies
Follicle-stimulating hormone (FSH)-containing gonadotropin preparations have been commercially available since the 1960s. Their first use was in ovulation induction in women with anovulatory disorders. Since 1978, however, after the first in vitro fertilization (IVF) baby was born, they have been used increasingly in assisted reproductive technologies (ART) such as IVF or intracytoplasmic sperm injection (ICSI) but also in intrauterine insemination (IUI) as ovarian stimulation to achieve multifollicular growth. Now, in many countries, ovulation induction stimulation comprises only 10% of gonadotropin usage, while 90% is used for ovarian (hyper) stimulation in ART, of which about half of the gonadotropin usage is for IVF and the other half is used for stimulated IUI cycles.
Laparoscopic ovarian drilling (LOD) is suggested as optional treatment in CC-resistant women with PCOS in all guidelines. Treatment with LOD does not result in more live birth and probably results in less live births when compared to letrozole. Laparoscopic ovarian drilling does result in less multiple pregnancies than gonadotrophins. On the other hand, using a strict cancellation protocol, lower multiple pregnancy rates can also be obtained in gonadotrophin protocols. Ovarian drilling appears safe but remains an invasive procedure with risk of adhesion formation. The required anaesthesia can be problematic in obese women, representing the majority of the PCOS population. LOD should therefore not be first choice fertility treatment in CC-resistant PCOS.
Infertility is defined by WHO-ICMART as a disease of the reproductive system defined as the failure to achieve a clinical pregnancy after 12 of more months of regular unprotected sexual intercourse. As all women lose their ability to conceive with age, this definition only holds within the womens’ reproductive age-span between the menarche and menopause. On average the woman’s fertility is highest in the early and mid-twenties, then slowly declines and drops even faster at 35 years and older.
This chapter reviews pharmacological agents with a focus on the clinical aspects of their use. There are two groups of pharmacological agents for ovarian stimulation: the first group includes injectable gonadotropins and the second group includes oral agents that are estrogen modulators. Enclomiphene is the more potent antiestrogenic isomer and the one primarily responsible for the ovulation-stimulation actions of clomiphene citrate (CC). It is important to stress the two main prerequisites for the success of CC ovarian stimulation: presence of reasonable estrogen levels in the body and an intact hypothalamic/pituitary axis capable of producing endogenous gonadotropins. Aromatase activity is present in many normal tissues, such as the ovaries, the brain, muscle, liver, breast tissue, as well as in pathological tissues such as malignant breast tumors. The short half-life of letrozole and absence of estrogen receptor antagonism result in a very favorable profile for infertility treatment compared with CC.