Here is a general list of what to avoid during pregnancy..
http://www.bygpub.com/natural/pregnancy.htm

As for skincare, I'll mention as much as I can think of, and hopefully others can chime in too!
Here is a kit we have designed especially for pregnancy! http://www.gardenofwisdom.com/catalog/item/7011943/7045356.htm

During pregnancy its usually best to stay as simple and natural as possible. But even natural can be unsafe. Depending on the ingredient.

ESSENTIAL OILS - Markey, and I both feel its probably best to avoid EO usage in general to be safe. Especially during the first 3 months of pregnancy. But I'd like to put a link here to help clarify this subject. http://www.naha.org/faq_pregnancy.htm
If there is ANY history of miscarriage at all, we suggest avoiding them altogether. Better safe than sorry.
I felt safe using various eo's during pregnancy, but there were many that I also totally avoided. But I'm trained in aromatherapy so I know which ones can be used and which ones cannot. What amounts, etc..
There are certain eo's that are however quite safe. (at under 1%) NEVER USE NEAT! This means never use Essential Oils undiluted! They are very concentrated plant essences, and should always be diluted.
We'll give a general list: orange eo, lemon eo, chamomile, mandarin, tangerine, neroli, rose, geranium, sandalwood, peppermint
Although we'd suggest to AVOID using peppermint and rose during the first 3 months. And don't forget that some of the citrus oils can be photosynthesizers. Especially the cold pressed ones. Distilled ones are not. But know what you are getting from your supplier, IF you are going to use them. 
Any that you want to use other than these, PLEASE RESEARCH THOROUGHLY!!
While there are others that are safe, you'd really want to be a trained aromatherapist to know what you're doing as this takes extensive research and learning.

The above said, we encourage anyone who is even considering using EO's during pregnancy to do thorough research on it first :)

HERBS - We suggest thorough research before using any herbs in pregnancy. We'd rather not suggest what you can and can't use.
However.. there are some that are absolutely wonderful for pregnancy! For instance red raspberry leaf is a great tonic to take your whole pregnancy. Not only is it high in iron and minerals, but it also helps to tone the uterus. Please research this as there is indeed herbs that are beneficial but its best you talk this through with your doctor as well!

CARRIER OILS - Oils we would suggest not using in pregnancy at this time is the Black Seed Oil (aka Nigella Sativa) and Neem Seed oil since there just isn't enough safety data.

HYDROSOLS - There is no known adverse affect from hydrosols topically. However, these are from herbs, plants and roots, and since hydrosol use is new we suggest you research to see which ones are suggested to use and which ones are not. We already have on the hydrosols chart page which ones that Suzanne Catty says not to use in pregnancy. So hopefully that will help too.  This is based on no known adverse effects but suggested based on their properties. A better to be safe than sorry approach.

Cosmetic ACIDS - We are going to err on the side of precaution on this one and suggest that acids be used sparingly in pregnancy. Most research out there will tell you that even glycolic is safe, but we would prefer to be on the safe side and not suggest glycolic. Absolutely do not use salicylic acid during pregnancy.  Lactic Acid in small amounts should be fine. Natural acids are still okay like fruit acids, vinegar (acetic acid) , vitamin C (l-ascorbic) etc.  If you do choose to use acids during pregnancy once again we encourage you fully research it before doing so.

Mandelic acid is the only one we consider safe, due to its small molecule size it cannot penetrate the skin into the bloodstream.

Do not use mandelic or lactic if your skin is sensitive, inflammed, cracked or if you have open sores.

Cosmetic ACTIVES - We would like to say exercise caution with these. Ingredients to absolutely avoid in pregnancy - viper venom (synake), Retinols, Retinoids, etc. Glycolic


ANY QUESTIONS PLEASE ASK!!