Twin pregnancy, fetal reduction and the 'all or nothing problem'

Pregnancy outcomes of fetal reduction in patients with intrauterine haematoma following double embryo transfer

RESEARCH QUESTION

Is there an association between intrauterine haematoma (IUH) and pregnancy outcomes in patients who undergo fetal reduction after double embryo transfer (DET), and if so, what is the relationship between IUH-related characteristics and pregnancy outcomes?

DESIGN

Clinical information and pregnancy outcomes of women who underwent fetal reduction after DET were analysed. Patients with other systematic diseases, ectopic pregnancy or heterotopic pregnancy, monochorionic twin pregnancies and incomplete data were excluded. Stratification of IUH pregnancies was undertaken based on IUH-related characteristics. The main outcome was incidence of fetal demise (<24 weeks), with other adverse pregnancy outcomes considered as secondary outcomes.

RESULTS

Thirty-four IUH patients and 136 non-IUH patients who underwent fetal reduction after DET were included based on a 1:4 match for age, cycle type and fertilization method. IUH patients had a higher incidence of early fetal demise (20.6% versus 7.4%, P = 0.048), threatened abortion (48.1% versus 10.3%, P<0.001) and postpartum haemorrhage (PPH; 14.8% versus 4.0%, P = 0.043) compared with non-IUH patients. IUH was an independent risk factor for early fetal demise [adjusted OR (aOR) 3.34, 95% CI 1.14-9.77] and threatened abortion (aOR 8.61, 95% CI 3.28-22.61) after adjusting for potential confounders. IUH pregnancies undergoing fetal reduction that resulted in miscarriage had larger IUH volumes and earlier diagnosis (both P < 0.03). However, IUH characteristics (i.e. volume, changing pattern, presence or absence of cardiac activity) were not associated with threatened abortion or PPH.

CONCLUSIONS

Fetal reduction should be performed with caution in IUH pregnancies after DET as the risk of fetal demise is relatively high. Particular attention should be given to IUH patients with early signs of threatened abortion and inevitable fetal demise.

Defending the de dicto approach to the non-identity problem

Is it wrong to create a blind child, for example by in vitro fertilization, if you could create a sighted child instead? Intuitively many people believe it is wrong, but this belief is difficult to justify. When there is a possibility to create and select either 'blind' or 'sighted' embryos choosing a set of 'blind' embryos seems to harm no-one since choosing 'sighted' embryos would create a different child altogether. So when the parents choose 'blind' embryos, they give some specific individual a life that is the only option for her. Because her life is worth living (as blind peoples' lives are), the parents have not wronged the child by creating her. This is the reasoning behind the famous non-identity problem. I suggest that the non-identity problem is based on a misunderstanding. I claim that when choosing a 'blind' embryo, prospective parents harm 'their child', whoever she or he will be. Put another way: parents harm their child in the de dicto sense and that is morally wrong.

Fetal reduction, moral permissibility and the all or nothing problem

There is an ongoing debate about whether multifetal pregnancy reduction from twins to singletons (2-to-1 MFPR) is morally permissible. By applying the all or nothing problem to the cases of reducing twin pregnancies to singletons, Räsänen argues that an implausible conclusion seems to follow from two plausible claims: (1) it is permissible to have an abortion and (2) it is wrong to abort only one fetus in a twin pregnancy. The implausible conclusion is that women considering 2-to-1 MFPR for social reasons ought to abort both fetuses rather than just one. To avoid the conclusion, Räsänen suggests that it is best to carry both fetuses to term and give one for adoption. In this article, I argue that Räsänen's argument fails for two reasons: the inference from (1) and (2) to the conclusion rests on a bridge principle that does not work in certain circumstances, and there is good reason to reject the claim that it is wrong to abort only one fetus.

Abortion and the veil of ignorance: a response to Minehan

In a recent JME paper, Matthew John Minehan applies John Rawls' veil of ignorance against Judith Thomson's famous violinist argument for the permissibility of abortion. Minehan asks readers to 'imagine that one morning you are back to back in bed with another person. One of you is conscious and the other unconscious. You do not know which one you are'. Since from this position of ignorance, you have an equal chance of being the unconscious violinist and the conscious person attached to him, it would be rational to oppose a right for detachment. Likewise, behind the veil of ignorance, it is rational to oppose abortions since you could be the fetus, Minehan claims. This paper provides a plausible reply to this argument.

The clinical outcomes of selective and spontaneous fetal reduction of twins to a singleton pregnancy in the first trimester: a retrospective study of 10 years

BACKGROUND

Singleton pregnancy is encouraged to reduce pregnancy complications. In addition to single embryo transfer (SET), selective and spontaneous fetal reduction (SEFR and SPFR) can also achieve singleton pregnancies. After SEFR or SPFR, an inanimate fetus remains in the uterus. It is unclear whether the inanimate fetus would adversely affect another fetus or the mother. Previous studies have focused on the differences between pre- and post-reduction. However, studies focusing on the influence of SEFR and SPFR on the remaining fetal development and maintenance of pregnancy are rare.

METHODS

Materials from 5922 patients whose embryo transfer dates ranged from March 2011 to January 2021 were collected. Both the SEFR group (n = 390) and SPFR group (n = 865) had double embryos transferred (DET) and got twin pregnancies, but subsequent selective or spontaneous fetal reduction occurred. The SET group (n = 4667) had only one embryo transferred. All were singleton pregnancies on the 65th day after embryo transfer. Clinical outcomes, including pregnancy outcomes, pregnancy complications, and newborn outcomes, were compared among the three groups.

RESULTS

After adjusting for age, infertility duration, types of infertility, states of embryos, body mass index, and factors affecting SET or DET decisions, multivariate regression analysis revealed that SEFR increased the risk of miscarriage (OR 2.368, 95% CI 1.423-3.939) and preterm birth (OR 1.515, 95% CI 1.114-2.060), and reduced the gestational age (βeta -0.342, 95% CI -0.544- -0.140). SPFR increased the risk of gestational diabetes mellitus (GDM) (OR 1.657, 95% CI 1.215-2.261), preterm premature rupture of membranes (PPROM) (OR 1.649, 95% CI 1.057-2.574), and abnormal amniotic fluid volume (OR 1.687, 95% CI 1.075-2.648). Both SEFR and SPFR were associated with reduced live birth rate (OR 0.522, 95% CI 0.330-0.825; OR 0.671, 95% CI 0.459-0.981), newborn birth weight (βeta -177.412, 95% CI -235.115--119.709; βeta -42.165, 95% CI -83.104--1.226) as well as an increased risk of low-birth-weight newborns (OR 2.222, 95% CI 1.490-3.313; OR 1.510, 95% CI 1.092-2.087).

CONCLUSIONS

DET with subsequent fetal reduction was related to poor clinical outcomes. We recommend that DET with subsequent fetal reduction should only be considered as a rescue method for multiple pregnancy patients with potential complications, and SET is more advisable.

Ethics of fetal reduction: a reply to my critics

In the article, Twin pregnancy, fetal reduction and the 'all or nothing problem', I argued that there is a moral problem in multifetal pregnancy reduction from a twin to a singleton pregnancy (2-to-1 MFPR). Drawing on Horton's original version of the 'all or nothing problem', I argued that there are two intuitively plausible claims in 2-to-1 MFPR: (1) aborting both fetuses is morally permissible, (2) aborting only one of the twin fetuses is morally wrong. Yet, with the assumption that one should select permissible choice over impermissible choice, the two claims lead to a counter-intuitive conclusion: the woman ought to abort both fetuses rather than only one. It would be odd to promote such a pro-death view. Begović et al discuss my article and offer insightful criticism, claiming, that there is no 'all or nothing problem' present in 2-to-1 MFPR. In this short reply, I respond to some of their criticism.

Twin pregnancy reduction is not an 'all or nothing' problem: a response to Räsänen

In his paper, 'Twin pregnancy, fetal reduction and the 'all or nothing problem', Räsänen sets out to apply Horton's 'all or nothing' problem to the ethics of multifetal pregnancy reduction from a twin to a singleton pregnancy (2-to-1 MFPR). Horton's problem involves the following scenario: imagine that two children are about to be crushed by a collapsing building. An observer would have three options: do nothing, save one child by allowing their arms to be crushed, or save both by allowing their arms to be crushed. Horton offers two intuitively plausible claims: (1) it is morally permissible not to save either child and (2) it is morally impermissible to save only one of the children, which taken together lead to the problematic conclusion that (3) if an observer does not save both children, then it is better to save neither than save only one. Räsänen applies this problem to the case of 2-to-1 MFPR, arguing ultimately that, in cases where there is no medical reason to reduce, the woman ought to bring both fetuses to term. We will argue that Räsänen does not provide adequate support for the claim, crucial to his argument, that aborting only one of the fetuses in a twin pregnancy is wrong, so the 'all or nothing' problem does not arise in this context. Furthermore, we argue that the scenario Räsänen presents is highly unrealistic because of the clinical realities of 2-to-1 MFPR, making his argument of limited use for real-life decision making in this area.

Trends of Selective Fetal Reduction and Selective Termination in Multiple Pregnancy, in England and Wales: a Cross-Sectional Study

Selective abortion was shown to be increasingly common in England and Wales over a 9-year period, occurring most frequently as twin to singleton reductions in the 1st trimester. We analysed the trends in selective abortion (SA) in multiple pregnancies in England and Wales between 2009 and 2018. This is a cross-sectional study looking at 1143 women with multiple pregnancies in England and Wales undergoing SA. There were a total of 1143 cases of SA between 2009 and 2018 in England and Wales, representing 0.07% of total abortions. There has been a steady increase in cases, from 90 in 2009 to 131 in 2018, with 82.3% justified under ground E of The Abortion Act 1967. The majority of SAs were carried out at 13–19 weeks gestation, and intracardiac injection of potassium chloride was the most prevalent method (75%). Twin to singleton reductions accounted for 59%, the most common form of SAs. Over half of all cases (59%) were performed in women aged 30–39 years, and 84% of all women were of White ethnicity. SA has been an option available for couples diagnosed with multiple pregnancy, especially when there are discordant anomalies. Although SA may decrease multiple pregnancy-related complications, preventative methods must be championed.