An increasing number of couples have been undergoing infertility treatments in recent years. In 2012, 0.9 million children were estimated to have been born using assisted reproductive technology (ART) [1], and the proportion of births through ART now exceeds 3% of all births in many industrialized countries [2]. Infertility treatment also influences a couple’s lifestyle and well-being by affecting the timing of childbirth and the balance between childbearing and labor force participation [3, 4].
However, a substantial proportion of couples choose to discontinue treatment before childbirth [5–8]. Dropping out, which can occur at any treatment stage, inevitably affects treatment success rates, an essential factor that is considered when evaluating the treatment efficacy [6]. Correspondingly, many previous studies have examined and identified several factors that lead people to discontinue infertility treatment. Several identified predictors of discontinuation are related to patients, clinics, and their relationships, including the patients’ physical and psychological burdens, their limited financial resources, inadequate organization of care, poor communication skills of staff, and negative interactions between the patients and staff [9–14]. Additionally, other studies have found that female age, duration of subfertility, other maternal conditions, and stressful life events were key factors in determining the success of the infertility treatment [15–18].
However, in comparison to these determinants of treatment failure and success, less is known about the chances of pregnancy after treatment discontinuation. This is, presumably, because clinics have limited information about patients who have dropped out of the treatment. Nevertheless, the possibility of pregnancy after treatment discontinuation cannot be excluded in advance and must be explicitly assessed for a more accurate evaluation of infertility treatments.
If the chances of pregnancy after treatment discontinuation are significant, it would imply that more attention should be given to patients who discontinue treatment. Indeed, a previous study that examined the long-term parenthood outcome after discontinuation of unsuccessful in vitro fertilization (IVF) treatment argued that “unsuccessful patients should not lose hope, because nearly half may subsequently succeed in having a child” [19]. It should be noted, however, that about half of the couples who achieved parenthood in this study did so through adoption. Moreover, the study did not examine the outcome of discontinuation at earlier treatment stages, that is, timed intercourse (TI) or artificial insemination with the husband’s semen (AIH).
The present study examined the largely understudied issue of the association between future pregnancy chances and dropping out of infertility treatments. Unlike most preceding studies, the data we collected for individuals who had experienced infertility treatment were obtained from a nationwide Internet survey. Using these data, we examined the probability of pregnancy after dropping out of infertility treatment, which were then divided into three stages: timed intercourse (TI), artificial insemination with the husband’s semen (AIH), and in vitro fertilization (IVF). We further investigated the factors that affected the patient’s decision to discontinue treatment and how the probability of pregnancy was associated with (i) a couple’s discontinuation experiences and (ii) a couple’s attributes.
Although the study findings are not free from limitations due to the use of self-reported experiences in infertility treatment, we expect our findings to have important implications for healthcare policy in advanced countries. This is especially the case in Japan, where 1 in 16.7 babies was born through ART in 2017 [20], still fewer than other advanced countries, and the total fertility rate dropped to 1.36 in 2019 after hovering slightly above 2.0 over the preceding seven years [21]. Additionally, the policy debate on public health insurance coverage for infertility treatment requires more information about the efficacy of the infertility treatment to evaluate whether financial support is necessary for subfertile couples.