Almost 40% of women in our sample experienced phantom foetal kicks after their first pregnancy, up to 28-years (average 6.8-y) post-partum, nearly 50% saying that they were very "convincing"

Sasan, Disha, Phillip G. Ward, Meredith Nash, Edwina R. Orchard, Michael J. Farrell, Jakob Hohwy, and Sharna Jamadar. 2019. “‘Phantom Kicks’: Women’s Subjective Experience of Foetal Kicks After the Postpartum Period.” PsyArXiv. November 11. doi:10.31234/osf.io/6qad9

Abstract: During pregnancy, a woman will attribute increased abdominal sensations to foetal movement. Surprisingly, many women report that they feel kick sensations long after the pregnancy, however this experience has never been reported in the scientific literature. Here, we show that almost 40% of women in our sample experienced phantom foetal kicks after their first pregnancy, up to 28-years (average 6.8-years) post-partum. Using a qualitative approach, we found that women describe the phantom sensations as ‘convincing’, ‘real kicks’ or ‘flutters’. Twenty-five percent of women described the experience as positive, and 27% reported felt confused or upset by the experience. Our results demonstrate that phantom kicks in the post-partum period are a widely experienced sensation, that may have implications for a woman’s post-partum mental health. The mechanism behind the phantom kick phenomenon is unknown, but may be related to changes in the somatosensory homunculus or proprioception during pregnancy.


Discussion

Here, we report the first scientific description of the phenomenon of postpartum phantom kicks. In this Australian sample, almost 40% of women reported experiencing kick-like sensations following their first pregnancy. Participants who experienced the sensations, described it as "real kicks" or "flutters", with nearly 50% saying that they were very "convincing". Most women commented on the nostalgia and emotion associated with the sensations. This is unsurprising given that pregnancy is an emotional experience due to the increased female sex hormones that result in increased sensitivity in women's emotional processing systems (11). Taken together, this evidence suggests that there may be an association between the emotional relationship to the baby and the sensations of phantom kicks. Despite this, we found no significant relationship between the kick-like sensations and reports of postpartum cognitive or emotional change. We therefore argue that these sensations are unlikely to be delusions, or hallucinations, or a result of postpartum depression, anxiety, or other mental health issues. Although we found no significant association between phantom kicks and postnatal depression or anxiety, our results suggest that the influence of phantom kicks on mood should not be neglected. Content analysis of women's responses to phantom kicks suggested that the experience could exacerbate symptoms of anxiety, particularly in the case of stillbirth. Additionally, the timing at which the phantom kicks begin could be detrimental to those overcoming depression or anxiety, without having any causal connection to mental health outcomes.


Potential explanations for the phantom kick phenomenon

The subjective experience of phantom kicks is apparently a common sensation post-pregnancy for many Australian women. At this stage, we can only speculate as to the origin or cause of the effect. Here, we will review relevant literature as potential avenues for future research. Attribution of 232 postpartum body recovery We considered the possibility that women could misattribute normal body recovery sensations to a phantom kick sensation. The postpartum restoration of muscle tone and connective tissue to the pre-pregnant state lasts for approximately 6 months (12) and most acute changes are resolved within the first 26 weeks (6 months) (6-months; 13). Thus, we repeated the analysis, excluding women who were 1-year post-birth and found that the frequency of phantom sensations did not change. Rather, in the full sample, 39.7% of women reported experiencing kick-like sensations. Excluding women 1-yr post-birth, 39.1% of women experience the sensations. We believe that in the months post-delivery, some sensations of phantom kicks are probably attributable to bodily recovery. However, as women continue to experience these sensations for many years, postpartum recovery cannot be the only contributor to the experience. Proprioception and Phantom Limbs Phantom kicks appear to have considerable similarities to phantom limb syndrome. Phantom limb syndrome occurs when individuals with a missing or amputated limb feel sensations that suggest the limb is still attached. People with phantom limb syndrome are often said to experience "real" movement (14) and pain (15, 16) suggesting that the phantom limb is still represented in proprioceptive body maps (15). The range of possible phantom phenomena is relatively broad (movement, pain, pins and needles, itching, pressure, etc.), suggesting that "kick" sensations could be possible. It is known that the female somatosensory cortex undergoes reorganisation following mastectomy (17). Around 33% of female mastectomy patients report phantom breast sensations, which emerge soon after amputation and continues up to 12-yrs post-surgery (18, 19). During pregnancy, the innervation of the abdominal region by ongoing foetal movement increases over the ~40week gestation, and rapidly ceases at childbirth. The rapid reduction of abdominal somatosensation at childbirth has some similarities to the rapid cessation of innervation following limb amputation. It is possible that phantom kicks may be phenomenologically like the phantom limb phenomenon.

Similarly, misattribution of normal bodily sensations might explain the phantom kick phenomenon. In the non-pregnant state, most spontaneous abdominal sensations are attributed to a digestive cause, and are likely not regularly attended to. During pregnancy, the largest and most salient 258 somatosensations in the abdominal area are quickly attributed to foetal movements. The mother pays close attention to these sensations and bonds with her baby and obstetric care providers direct her to pay close attention to any reduction in the frequency of movements (e.g., 20). Thus, the mother's self-model of her body, and the origin of sensations within it, is updated. Following childbirth, and the subsequent "resettling" of the body organs to the non-pregnant state, there is a substantial reduction in abdominal innervations. It is no longer appropriate to attribute abdominal sensations to the foetus. Perhaps women who experience phantom kicks do not re-update their conceptual model of the body following childbirth, and attribute normal (digestive) sensations to a foetus that is no longer there. Implications of Results for Peri-Natal and Post-Partum Care Due to our sampling method, we cannot make statements of prevalence of phantom kicks in the postpartum period, but we can say that phantom kicks appear to be a common experience among women following the birth of their first child. In our sample, two in every five women experienced the phenomenon. The experience was described as negative for some women, during a period of high vulnerability for mood disorder and mental illness. Around 16% of participants commented that the experience of phantom kicks was negatively impacting on their wellbeing. Many women described a lack of information and expertise being made available to assuage their fears during a crucial time. The field of medical science should address this shortcoming and inform health care providers of the potential risk that unexpected and unexplained phantom kick sensations may pose.

Women are routinely directed to pay attention to foetal kick rate during late pregnancy, either through the media (e.g., 21), or as directed by their health care provider (20). For example, the Royal College of Obstetricians and Gynaecologists (20) guidelines state that .Women should be advised of the need to be aware of foetal movements up to and including the onset of labour and should report any decrease or cessation of foetal movements to their maternity unit. and that "A significant reduction or sudden alteration in foetal movement is a potentially important clinical sign." Our results raise an intriguing question: if women report sensations of foetal movement postpartum in the absence of a 283 foetus, how reliable is the perception of foetal kicks during pregnancy? In other words, are all maternal perceptions of foetal kicks attributable to the foetus? Early research using Doppler ultrasound suggested that not all maternal perceptions of movement were detectable using ultrasound: Johnson, Jordan, and Paine (22) found that 12% of maternal sensations of foetal movement were undetected by ultrasound. Recent studies with newer technology show great individual variability in maternal perception of foetal movement, between 2.4 to 81% (23). An interesting corollary of the current study is that perhaps not all sensations attributed to foetal movement during pregnancy is due to the foetus. This result therefore has implications for the reliability of maternal perception as an indicator for reduced foetal movement and subsequently foetal health. It may be useful in future studies of maternal perceptions of antenatal foetal kicks to use a psychophysiological approach (e.g., Signal Detection theory, 24) to systematically quantify the occurrence of hits, misses, false positives and false negatives of abdominal interoceptive signals.

In sum, our study suggests that up to 2 in 5 women experience sensations of foetal movement long after childbirth and the postpartum period. These sensations may have implications for the mother's mental health during a vulnerable time. We have explored potential explanations for the phenomenon to assist in generating hypotheses for further research. Through this study, we hope to build awareness relating to phantom kicks that will ensure that women are given the appropriate information and care they require. Obstetric, gynaecological, and mental health clinicians specialising in postpartum care should be aware of the potential impact that phantom kicks may have on their clients, especially those that experience abortion, miscarriage, stillbirth, or traumatic birth.