An international internet survey of the experiences of 1,714 mothers with a late stillbirth: the STARS cohort study

Our findings agree with other published reports [20‐22] that women who have experienced a stillbirth had a gut instinct that things may be amiss with the pregnancy, sometimes well, prior to their baby’s death. There have been no investigations of this kind in women who have had a live birth and it is probable that recall and negativity biases are very likely at play with respect to this finding. However, it is particularly noteworthy that more than two thirds of the participants who answered this question answered in the affirmative, with many recalling having these feelings from the beginning of their pregnancy and mentioning this to others well before their baby’s death. We considered that this “intuition” was associated with experience of prior pregnancies and postulated therefore that it would be more frequently reported in multiparous women however, both nulliparous and multiparous participants reported these feelings in roughly equal proportions, indeed the percentage was slightly higher in the nulliparous group. We further hypothesised that participants might have processed their feelings over time and that therefore women reporting a gut instinct might slowly increase over time; however, reports of a gut instinct were highest in the women who had a stillbirth less than 6 months ago and remarkably stable beyond the initial 6 months. Further research should therefore be initiated to explore this phenomenon, a prospective study would identify the proportion of women with this “gut instinct” in pregnancies that have a successful outcome and confirm or not the importance of identifying this feeling during pregnancy. In the meantime this maternal intuition may be something for care providers to pay attention to. We therefore suggest that if pregnant women report these feelings that they should be taken seriously and that if care providers sensitively ask them if they have these kinds of feelings, it may alert both the woman and the maternity care provider to be watchful and mindful of other ominous signs such as alteration in fetal movements or slowing fetal growth.

There is emerging evidence that events occurring during sleep may impact pregnancy outcome. Such events include supine sleep position [23‐25], sleep disordered breathing [26] and poor sleep quality [27, 28], all of which affect a large proportion of pregnant women. While 28 % of women were unable to estimate the time of day the baby died, of the remainder, deaths were perceived to occur most frequently during the night. These findings are remarkably similar to those found in the ‘Sydney stillbirth study’ [25] where a little over 50 % of the 103 participants who had a recent stillbirth considered that their baby had died overnight. This further raises the possibility that events which occur during sleep may be important in relation to stillbirth in addition to the adverse pregnancy outcomes previously reported. Even so, events that occur during sleep may impact pregnancy outcome irrespective of the time of death. For example sleep disordered breathing is independently associated with maternal hypertension [29‐34], as well as with fetal growth restriction [32, 35, 36], both of which are known risk factors for stillbirth, hence these sleep related events may, in combination, [37] be associated with stillbirth even though the stillbirth itself may not have occurred during the night. Additionally the mother may not always know exactly when the death occurred.

There was fair agreement between what the participants believed caused their baby’s death and what they recall being told caused their baby’s death by their care provider. Interestingly, this is better than the Kappa value between stillbirth certificates and the COD determined by expert review (K = 0.29) [38].

It is also interesting to note the number of participants who believed (n = 428; 25.0 %) or were told (n = 457; 26.7 %) that their baby’s death was due to a cord accident of some kind, i.e., true knot, nuchal cord, or cord entanglement. This was greater than that reported in large cohort studies [39, 40]. Unfortunately, the fact that we were asking bereaved mothers about cause of death meant that we could not ask more detailed clinical questions other than what the participants offered in comment. Hence details such as degree of tightness, length of cord, amount of Wharton’s jelly, were not able to be elucidated.

Nuchal cords occur in up to 30 % of uncomplicated pregnancies and they have not been found to be associated with an increased risk of stillbirth [41]. Similarly, true knots also are quite common in live births and in order for the true knot to be implicated as the COD, demonstration of constriction of the umbilical vessels or evidence thrombosis is necessary [42]. Therefore gross cord problems (nuchal cord, true knot) in and of themselves are not usually considered the antecedent COD unless there is demonstration of vascular thrombosis/avascular villi in the placenta/fetal vessels. Nevertheless, cord-related stillbirths may be underdiagnosed. For example in a small study, when placental histologic criteria were applied to a series of 62 stillbirths, 42 % met the criteria for cord accident [43]. Therefore, it may be that a higher percentage of late stillbirths are actually caused by cord issues than is currently being attributed.

In the case where the participants believed that their baby died as a result of a cord accident and they were told something else, perhaps they did not believe or understand what their care provider told them or remembered that the cord was mentioned. Further, if they were told that the COD was unknown or the attributed cause was in some way unacceptable to them, it may be that they have adopted the belief that the cord was responsible as a means of plausible explanation either to themselves or their family and friends. Perhaps the care provider chose to implicate the cord as the COD because they considered it may be more simply understood as a physical barrier to fetal blood flow.

As well as the marked increase in the number of reported cord accidents participants also reported all COD, as told to them by their care provider, at frequencies significantly different from most perinatal mortality reports from high-income countries (e.g. [44, 45]). There was substantially less infection, and obstetric condition causes than would be expected. This may reflect exclusion of stillbirths <28 weeks gestation which are more likely to have signs of infection [46].

Conventional autopsy is considered the diagnostic gold standard, because it can confirm or augment antemortem findings, fulfil the need for parental information, assist with future planning as well as provide answers about what had happened [47]. A full autopsy can provide a diagnosis, change the antemortem clinical diagnosis, or reveal additional findings in up to 58 % of cases [47]. However, the rates of perinatal autopsy have steadily fallen worldwide, for example in the UK between 2000 and 2007, consent for perinatal autopsy declined from 55 % to 45 %, with parental objection as the main cause for conventional autopsy not being done [48]. The frequency of full autopsy in our study is comparable with this and other studies [49, 50]. It may be that in the absence of autopsy, as was the case in half of our sample, the COD as told by the care provider may be considered as unreliable as parental belief about what caused their baby’s death.

Of concern is the number of participants (n = 138; 8.1 %) who believed that their care provider played a role in their baby’s death. Although we acknowledge that there may be justification for some parents to blame their care provider, that so many reported that their care provider played a role in their baby’s death could reflect that maternal concerns in the antenatal or intrapartum period were not addressed [14] or indicate a lack of thorough debriefing and counselling after the stillbirth. Alternatively, it is even possible that a care-giver apology may have been warranted [51].

It is quite heartbreaking that almost five percent of the participants (n = 80) considered they played a role in their baby’s death especially since many reported highly unlikely and biologically implausible reasons for the stillbirth. This may reflect the high-levels of guilt often perceived by mothers after stillbirth [52].

Overall, whilst there was fair agreement (Kappa) between what the participants said they were told and what they believed was the COD it would seem likely that many of the participants either did not believe what they were told, believed that they were told something that they actually were not, or chose to believe something else. Our findings suggest that care providers delivering COD information should perhaps explore with parents what they believe was the COD in order to provide reassurance and a thorough counselling/debriefing following their stillbirth.

The retrospective nature of this study, participant perception, recall and negativity biases and self-selection of participants are all limitations to this study which should be taken into consideration when interpreting the results. Furthermore, women had to have access to the internet and therefore many have access to more information about factors that are believed to be associated with stillbirths e.g. reduced fetal movements [53]. Therefore, future studies to further explore our findings should ideally either be prospective or controlled.

In spite of the above limitations this study also has a number of strengths. Data were collected from a large number of women from across the globe, including low and middle-income countries. The surveys were completed anonymously and this may have encouraged a degree of honesty that may be greater than in a face-to-face interview, particularly demonstrated by the number of women who indicated that they believed they played a role in their baby’s death.

The study population was mainly well-educated women living in high-income countries who were able to use English and with access to the internet. Therefore, these results may not be generalizable to other populations. As the COD of late stillbirths are very different in low and middle-income countries these results may not be generalizable to these settings. Further studies are needed in these high-burden regions (Additional file 4).