Hi I have a beighton score of 8 or 9, depending on the consultant!!! Yes the sciatica could very well be related. With hypermobility syndrome affecting the collagen when pregnant the pregnancy hormones soften the ligaments to allow an easy passage for the baby through the birth canal, therefore for people with hypermobility ligaments that are already more stretchy become even more so which can cause more joint problems and pain.
I am not too sure as to why there is an increased risk of premature labour and I only found this out after the prem birth of my second child. I do know that here can be problems with epidural anaesthetics due to being hypermobile, I was unfortunate to experience this and nothing and no-one could EVER convince me to have another epidural!
If you are hypermobile it would definitely be a benefit to speak to your midwife and even your rheumatologist about any effects pregnancy can have. The hypermobility syndrome association have a help line as well and they can be very helpful.
I am pleased that I have started this post as I would have benefited from being aware of the problems that can be associated with pregnancy/childbirth and hypermobility syndromes.
I have not been officially diagnosed with the condition, and probably don't qualify on the Brighton scale as I haven't suffered from arthralgia for greater than 3/4 months, although it would explain why I seem to be so prone to back (particulalry around my shoulder blades) and knee problems! I even had a jaw ligament problem a while back which meant I couldn't open my mouth properly and I had to see an oral surgeon and I read somewhere that this could be related too. I have always been aware that my joints are a bit 'funny' (hubby jokingly calls me a freak of nature sometimes-good job I can take a joke!) but have only recently started to look into it a bit more. I am probably just classed as having hypermobile joints, not the syndrome, but I guess when combined with pregnancy hormones it could become an issue. I will definitely discuss it with my GP. I need to see her anyway because the sciatica is now getting so painful by bedtime that I can't put any weight on my left leg. I'm starting aqua natal classes tonight and hoping that might help and give me some relief.
Thanks so much for posting this thread and for the information you have provided!