Introduction
Medication use in pregnancy is becoming increasingly common where a 68% rise has been reported in the United States of America in the past 30 years, likely due to increasing maternal age and associated increased risk of comorbid medical conditions (1). One systematic review revealed a wide variation amongst developed countries where 27% to 93% of pregnant women were on prescription drugs excluding multivitamins. Prevalence was higher in France (93%) and lower in Northern European countries (44-47%) (2). A cohort study of 106,000 pregnancies in Norway between 2004 and 2006 found that 83% of mothers were on prescription drugs between 3 months prior to conception and 3 months after giving birth (3). On average each mother was prescribed 3.3 medications and the most common were antibiotics and respiratory medications. Furthermore 25% of fathers were on prescription drugs over the same time frame, in particular anti-inflammatory medications for musculoskeletal disease. Another study examined specific drugs used across both pregnant and non-pregnant women in United States and there was a marked age discrepancy where younger women (aged 25-34 years) were more likely to take beta blockers and non-steroidal anti-inflammatory medications whereas older women (aged 35-44 years) were more likely to be taking antidepressants and levothyroxine (see Table 1 ) (4).
Currently, nearly 3% of all babies born in the UK each year are born due to ART(5). There have been over 1,103,000 IVF cycles performed in the UK since 1991. In 2016 alone, there were over 68,000 IVF cycles, resulting in 20,028 births(6). The overall trend is that IVF cycles and births have been increasing year on year since 1991 and is projected to increase even further. The average age of women undergoing ART in the UK is 35.5, with the average age of women in natural pregnancy being 30.3 years (5, 7). Information on the prevalence of prescription drug use amongst couples undergoing ART is limited and there are even less studies available on medications taken by the male partner specifically. Importantly, paternal factors do contribute equally towards the epigenome and therefore prescription drug use in men may impact the quality of sperm, fertilisation, implantation and embryo development (8, 9).
As many patients undergoing ART are older, they may be more likely to be on more prescription medication than the rest of the child-bearing-age population. Numerous studies demonstrate common conditions that have a rising prevalence with age, including depression and/or anxiety, hypothyroidism and type 2 diabetes (10, 11). It is therefore more likely that these women will be on prescription medication for these conditions when they undergo ART. ART currently only has a success rate (defined as ‘live births per ART cycle’) of approximately 33% in the UK therefore it is important that any additional risks from these medications on reproductive outcomes are clarified, advising future practice and enabling couples to make an informed decision about medication use (5). Minimising the risk of failed ART and/or foetal loss but also the aforementioned teratogenic side effects of drugs is of maximal importance.
Therefore we performed this narrative review of the current evidence on prescription drug use to treat co-morbid health conditions in both women and men undergoing ART. This review could then form a counselling tool for clinicians to better discuss with their patients the impact of specific medications for men and women having ART and guide clinical decision making.