I would also like to add my experience here. I have one healthy boy but had an early miscarriage in the beginning of the year, so have been pretty nervous in the first stages of this pregnancy. When we went in for our dating scan at 11 weeks baby had an enlarged bladder. CRL was 51 mm and longitudinal bladder length 7.4 mm. Our midwife told us not to worry (and not to google) and that 9 out of 10 cases resolve spontaneously. Needless to say we did google before we even left the room and that got us pretty worried... We were immediately referred to a specialist foetal medicine unit, who fortunately could see us the next day.
I am a medical researcher myself and searched the scientific literature, which, as was mentioned by others, is pretty limited. Enlarged bladder or megacystis is very rare and I could find only 3 larger studies on first trimester diagnosis and outcome of this condition: Liao et al. 2003, Kagan et al. 2010 and Fontanella et al. 2017 (first two are reviewed in Taghavi et al. 2017). I read the papers dozens of times, looked at all the defined categories and stats. A longitudinal bladder length of less than 15 mm meant a 25% chance of chromosomal abnormalities, mainly trisomy 13 & 18 and, if karyotype was normal, a 90% chance of spontaneous resolution. In the foetal medicine unit nuchal translucency (NT), nasal bone and abdominal wall were assessed. NT was normal, nasal bone was present and abdominal wall closed - all good signs in relation to potential karyotypic abnormalities. We were offered a chorionic villi sampling (CVS) test, which beforehand I would have refused because of the risk of miscarriage, but when you're faced with a 1/4 chance of trisomy, the added risk of 1/500 for CVS-induced miscarriage suddenly seems trivial. CVS went smoothly and after a week of anxious waiting we received the first results: karyotype was normal and we were expecting a boy! That in itself was such a huge relief that I cried, the first hurdle taken. Early megacystis is more common and has a better prognosis in boys than girls.
Then came the 4 week long wait for our next scan, at 16 weeks and again at the foetal medicine unit. I was super nervous and anxious, but quickly released from the stress when our gynaecologist said the bladder now was completely normal! There was no evidence of kidney damage and everything else looked fine. Again tears of joy and relief, only then I realised what kind of stress I had been under during the past 5 weeks. We will still have an extensive ultrasound examination at the foetal medicine unit at 20 weeks to look into more detail at the kidneys. From what has been published, if there is spontaneous resolution of first trimester enlarged bladder before 23 weeks there are no lasting effects after birth. I will slowly allow myself to start enjoying this pregnancy, although I realise now more than ever that things can go wrong at any stage...
Holding on to the stats from larger cohort studies and reading this thread over and over again kept me going during this awfully stressful period and by sharing our experience I would like to offer some hope and support to any future parent having to go through this.
I am a medical researcher myself and searched the scientific literature, which, as was mentioned by others, is pretty limited. Enlarged bladder or megacystis is very rare and I could find only 3 larger studies on first trimester diagnosis and outcome of this condition: Liao et al. 2003, Kagan et al. 2010 and Fontanella et al. 2017 (first two are reviewed in Taghavi et al. 2017). I read the papers dozens of times, looked at all the defined categories and stats. A longitudinal bladder length of less than 15 mm meant a 25% chance of chromosomal abnormalities, mainly trisomy 13 & 18 and, if karyotype was normal, a 90% chance of spontaneous resolution. In the foetal medicine unit nuchal translucency (NT), nasal bone and abdominal wall were assessed. NT was normal, nasal bone was present and abdominal wall closed - all good signs in relation to potential karyotypic abnormalities. We were offered a chorionic villi sampling (CVS) test, which beforehand I would have refused because of the risk of miscarriage, but when you're faced with a 1/4 chance of trisomy, the added risk of 1/500 for CVS-induced miscarriage suddenly seems trivial. CVS went smoothly and after a week of anxious waiting we received the first results: karyotype was normal and we were expecting a boy! That in itself was such a huge relief that I cried, the first hurdle taken. Early megacystis is more common and has a better prognosis in boys than girls.
Then came the 4 week long wait for our next scan, at 16 weeks and again at the foetal medicine unit. I was super nervous and anxious, but quickly released from the stress when our gynaecologist said the bladder now was completely normal! There was no evidence of kidney damage and everything else looked fine. Again tears of joy and relief, only then I realised what kind of stress I had been under during the past 5 weeks. We will still have an extensive ultrasound examination at the foetal medicine unit at 20 weeks to look into more detail at the kidneys. From what has been published, if there is spontaneous resolution of first trimester enlarged bladder before 23 weeks there are no lasting effects after birth. I will slowly allow myself to start enjoying this pregnancy, although I realise now more than ever that things can go wrong at any stage...
Holding on to the stats from larger cohort studies and reading this thread over and over again kept me going during this awfully stressful period and by sharing our experience I would like to offer some hope and support to any future parent having to go through this.
